Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Walter Energy (NYSE: WLT) jumped 10% briefly today on more buyout rumors.

So what: Yesterday, shares jumped on a report out of London's Independent that BHP Billiton (NYSE: BHP) or Anglo American were preparing bids to buy the company. Today, Australia's newspaper The Australian stoked the fire and continued yesterday's speculation.

Now what: There wasn't a lot of new information in The Australian article, so investors buying on that news are a little late to the party. But like I said yesterday -- buying simply on rumor is a terrible way to invest.

Analysts did react last night and don't seem to think the Walter/BHP deal makes a lot of sense; shares have been selling off all day. The euphoria is starting to die, and I don't see shares holding at elevated levels unless a deal is actually announced.

Interested in more info on Walter Energy? Add it to your watchlist by clicking here.